/*
* RapidMiner
*
* Copyright (C) 2001-2010 by Rapid-I and the contributors
*
* Complete list of developers available at our web site:
*
* http://rapid-i.com
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see http://www.gnu.org/licenses/.
*/
package com.rapidminer.test;
import static junit.framework.Assert.assertEquals;
import org.junit.Test;
import com.rapidminer.tools.math.MathFunctions;
/**
* A test for the {@link MathFunctions}.
*
* @author Michael Wurst, Ingo Mierswa
*/
public class MathUtilsTest {
@Test
public void testVariance() {
assertEquals(MathFunctions.variance(new double[] { 0.1, 0.1, 0.0, -0.1 }, Double.NEGATIVE_INFINITY), 0.006875, 0.001);
assertEquals(MathFunctions.variance(new double[] { 0.0, 0.0, 0.0 }, -1.0), 0.0);
}
@Test
public void testCorrelation() {
assertEquals(MathFunctions.correlation(new double[] { 0.1, 0.2, -0.3, 0.0 }, new double[] { 0.0, 0.1, 0.1, -0.1 }), -0.161, 0.001);
}
}